【摘要】 基于超声波在层状介质中传播规律,建立理论声压透射系数Tp与材料弹性模量E的相关性.采用超声水浸技术测定微米厚薄板的双透射信号,通过信号分析获得实验声压透射系数Te,应用非线性最小二乘法反演薄板的弹性模量,并与声速法测量得到的弹性模量进行比较.结果表明:将反演的弹性模量代入到Tp中,发现在有效频带范围内Tp与Te吻合较好;反演获得的弹性模量值与声速法测定结果较接近,偏差介于1.4%和8.2%之间;实验证明了该方法可作为薄层材料弹性模量检测方法的一种补充.更多还原

【Abstract】 The correlation between the acoustic pressure transmitting coefficient and elastic modulus of the material was established according to the law of ultrasonic wave propagating in the layered medium.The double-transmission signal was obtained by ultrasonic immerse-water technique and the acoustic pressure transmitting coefficient was measured by means of signal analysis.By the application of nonlinear least-squares optimization technique,the elastic modulus of the sheet metal was inversed and compared with those obtained by the velocity method.The results show that: theoretical values of the acoustic pressure transmitting coefficient are consistent with the experimental data,the values of elastic modulus obtained by the inversion method have a good agreement with the results of the velocity method,and the deviation lies between 1.4% and 8.2%.Therefore,this method can be a supplement for the measurement of elastic modulus of lamellar materials.更多还原